package com.ustcinfo.study.mr.zhangqing;

import java.io.IOException;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;

public class MyWorldCount {
private static class MyMapper extends Mapper<Object, Text, Text, IntWritable>{
	private static final IntWritable count = new IntWritable(1);

	@Override
	protected void map(Object key, Text value,Context context)throws IOException, InterruptedException {
		String line = value.toString();
		String[] starr = line.split(" ");
		for (int i = 0; i < starr.length; i++) {
			Text text = new Text();
			text.set(starr[i]);
			context.write(text, count);
			
		}
		
	}
}

private static class MyReducer extends Reducer<Text, IntWritable, Text, IntWritable>{
	@Override
	protected void reduce(Text key, Iterable<IntWritable> values,Context context) throws IOException, InterruptedException {
		// TODO Auto-generated method stub
		int sum = 0;
		for (IntWritable intWritable : values) {
			sum+=intWritable.get();
		}
		context.write(key, new 	IntWritable(sum));
	}
}

public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {
	Job job = Job.getInstance();
	job.setJobName("zq_test");
	job.setJarByClass(MyWorldCount.class);
	job.setMapperClass(MyMapper.class);
	job.setCombinerClass(MyReducer.class);
	job.setReducerClass(MyReducer.class);
	job.setOutputKeyClass(Text.class);
	job.setOutputValueClass(IntWritable.class);
	 FileInputFormat.addInputPath(job, new Path(args[0]));
     FileOutputFormat.setOutputPath(job, new Path(args[1]));
     int status = job.waitForCompletion(true) ? 0 : 1;
     System.exit(status);	
  }
}
